WO2019130389A1

WO2019130389A1 - Vapor deposition mask, vapor deposition method, and production method for organic el display device

Info

Publication number: WO2019130389A1
Application number: PCT/JP2017/046412
Authority: WO
Inventors: 克彦岸本
Original assignee: 堺ディスプレイプロダクト株式会社
Priority date: 2017-12-25
Filing date: 2017-12-25
Publication date: 2019-07-04
Also published as: US10876199B2; JP6496086B1; US20200263287A1; CN111492089A; JPWO2019130389A1; US20210071289A1

Abstract

Provided is a vapor deposition mask that suppresses heat conduction at a frame thereof, that achieves weight reduction, and that can tolerate high stress at a portion of the frame to which particularly high stress is applied. The present invention has: a mask main body (10) at which an opening pattern is formed; and a frame (15) to which at least a portion of a peripheral edge part of the mask main body is joined. At least a portion of the frame is formed as a rod-like lateral frame (15b) that is formed by laminating, via connection surface plates (153), unit structures (155) for a sandwich structure in which a surface plate (152) is stuck to a surface that faces at least portions of core parts (151) that contain gaps.

Description

Vapor deposition mask, vapor deposition method, and method of manufacturing organic EL display device

The present invention relates to, for example, a deposition mask for depositing an organic layer of an organic EL display device, a deposition method, and a method of manufacturing an organic EL display device.

When an organic EL display device is manufactured, drive elements such as TFTs are formed on a substrate, and an organic layer is laminated corresponding to each pixel on the electrode. This organic layer is weak to moisture and can not be etched. Therefore, for example, as shown in FIG. 8, the organic layer 80 is formed by stacking the deposition target substrate 81 and the deposition mask 82 consisting of the mask main body 821 and the frame 822, and depositing through the opening 821 c of the deposition mask 82. This is done by depositing the organic material 85a of the source 85. Then, the necessary organic layer 80 is stacked only on the electrode 81 a surrounded by the insulating film 81 b of the necessary pixel. If the deposition substrate 81 and the deposition mask 82 are not as close as possible, the organic layer 80 is not formed only in the precise region of the pixel. If the organic material is not deposited only in the correct pixel area, the displayed image is likely to be unclear. Therefore, the metal support layer 821b of magnetic material is used for the vapor deposition mask 82, and the vapor deposition is performed between the permanent magnet 83 or electromagnet and the vapor deposition mask 82, which are arranged fixedly with resin 84 on the opposite surface of the vapor deposition substrate 81. By interposing the substrate 81, a method of a magnetic chuck for bringing the deposition substrate 81 and the deposition mask 82 close to each other is used (see, for example, Patent Document 1).

Although a metal mask was conventionally used as a vapor deposition mask, the use of a hybrid type mask body 821 in which the resin film 821a and the portion excluding the periphery of the opening 821c of the resin film 821a are supported by a metal support layer 821b It began to be considered. The vapor deposition mask 82 is fixed to the frame 822 at the peripheral portion of the mask main body 821 so that the mask main body 821 can be stabilized and the handling becomes convenient. In FIG. 8, reference numeral 821 d denotes an opening of the metal support layer 821 b which is formed larger than the opening 821 c so as not to close the opening 821 c of the resin film 821 a. The peripheral portion of the metal supporting layer 821 b is fixed by welding or the like to a frame (frame body) 822 formed of a metal made of invar or the like having a small coefficient of thermal expansion.

JP, 2014-205870, A

As described above, the deposition mask 82 is bonded to the frame 822 at the periphery of the mask body 821. However, as apparent from FIG. 8, the frame 822 is closest to the deposition source 85 during deposition. Therefore, the temperature of the frame 822 is most likely to rise, the heat of the heated frame 822 is transmitted to the mask main body 821 of the deposition mask 82 and the deposition target substrate 81, and the temperature of the deposition target substrate 81 also tends to rise. Since the frame 822 is pure and heavy, the heat capacity is also increased, so it is easy to maintain the temperature once it has risen. As a result, the temperature of the deposition substrate 81 is likely to be higher at the peripheral portion than at the central portion. That is, a difference in the thermal expansion of the deposition target substrate 81 occurs, and there is a problem that the uniform organic layer 80 can not be formed.

In particular, the problem of the temperature distribution becomes remarkable as the deposition substrate and the deposition mask become larger. However, the deposition mask is also required to be further enlarged from the viewpoint of cost reduction due to mass production. That is, the largest vapor deposition substrate size (so-called mother glass size) in the present organic EL manufacturing process is G6H (half size of the sixth generation (about 1500 mm × 1800 mm), ie, about 1500 mm × 900 mm), The size of the mother glass used in the preceding liquid crystal panel manufacturing process is over G10 (about 2880 mm × 3130 mm), and even in the case of an organic EL display device, the demand to realize further enlargement is strong . However, in the manufacturing process of the organic EL display device, it is considered difficult to make the deposition substrate size larger than G6H. One of the causes is the weight of the deposition mask.

Regarding the weight, the weight of the frame is about 80 kg even with the size of G6H described above, and this weight is close to the limit of the transfer of the deposition mask by the robot arm and can not be made heavier than this. However, from the viewpoint of preventing positional deviation between the deposition mask and the deposition substrate due to thermal expansion during deposition, the material of the frame of the deposition mask is a material with a small linear expansion coefficient, and the mask body is tensioned. In consideration of jointing, there is a restriction that the frame can not be made thinner or thinner than now. Therefore, it can not be changed to a lightly light material.

The present invention has been made to solve such problems, and by suppressing the heat conduction in the frame of the deposition mask and reducing the weight, the deposition mask can be made larger and the height can be increased. While the fine deposition can be performed at low cost, the above-mentioned weight and heat while being resistant to a large stress, particularly for a frame where a particularly large stress is applied on each side of the frame-like deposition mask It is an object of the present invention to provide a deposition mask satisfying the requirements for conduction and a deposition method using the deposition mask.

Another object of the present invention is to provide a method of manufacturing a large-sized organic EL display device excellent in display quality by using the above vapor deposition method.

The vapor deposition mask according to the first embodiment of the present invention comprises a mask main body having an opening pattern formed thereon, and a frame which is joined to at least a part of the peripheral portion of the mask main body to hold the mask main body in a constant state. And at least a part of the frame is formed by laminating, via a connecting face plate, a unit structure of a sandwich structure in which a face plate is attached to an opposing surface of at least a portion of a core portion containing an air gap. It is formed in a columnar body.

In the vapor deposition method of the second embodiment of the present invention, there is provided a step of disposing the vapor deposition substrate and the vapor deposition mask so as to overlap with each other, and a vapor deposition material from a vapor deposition source disposed apart from the vapor deposition mask. Depositing the vapor deposition material on the vapor deposition substrate by scattering.

In the method of manufacturing the organic EL display device according to the third embodiment of the present invention, at least the TFT and the first electrode are formed on the support substrate, and the organic material is deposited on the support substrate using the vapor deposition method. Forming a laminated film of an organic layer, and forming a second electrode on the laminated film.

According to the present invention, since the unit structure having a sandwich structure in which the face plate is attached to at least a part of the facing surface of the core portion is laminated through the connection face plate, the column body is formed. Sufficient rigidity can be obtained even when a large stress is exerted in the axial direction of the frame. That is, for example, it is known that a unit structure of a honeycomb structure has sufficient rigidity against a large stress in a direction parallel to the axial direction of a hexagonal through hole, but this unit structure By being stacked so that the direction of the axis of the through holes is aligned, the body exerts rigidity even against very large stress. That is, although it is very difficult to manufacture a honeycomb structure having a through hole in the axial direction in one piece, even if it can be made long, the buckling strength is reduced, so that a large stress can not be obtained. I can not bear. However, if it is a columnar body formed by making it a layered product of unit structure, even if it becomes long, it can endure enough to a big stress.

Furthermore, the weight is greatly reduced by providing a sandwich structure having a void. In addition, the formation of the air gap can significantly suppress the heat conduction, and can significantly suppress the heat conduction by the radiation from the deposition source during the deposition. Furthermore, since the heat capacity is also reduced by weight reduction, heat accumulation can be suppressed even when vapor deposition is continuously performed while replacing the deposition target substrate.

It is a figure which shows the schematic top view of the vapor deposition mask of one Embodiment of this invention. It is an IB-IB sectional view of Drawing 1A. It is the figure seen from arrow C of FIG. 1A. It is the figure seen from the arrow D of FIG. 1A. It is a figure which shows an example which produces a columnar frame from the unit structure of sandwich structure. It is a figure which shows an example which produces the laminated body of the unit structure of sandwich structure. It is a figure which shows the other example of the laminated body of FIG. 2B. It is a figure which shows the manufacturing process of an example which manufactures a honeycomb structure. It is a figure which shows the manufacturing process of an example which manufactures a honeycomb structure. It is a figure which shows the manufacturing process of an example which manufactures a honeycomb structure. It is a perspective view which shows the core part of FIG. 3C. It is a perspective view when the core part of FIG. 3C is formed with CFRP material. It is a figure explaining the anisotropy in the case of manufacturing CFRP material by injection molding. It is another structural example of a sandwich structure. It is an enlarged view of the connection part of the core and face plate of FIG. 4A. If it is a honeycomb structure, it is a figure explaining the reason strong against the force of a horizontal direction. It is a schematic side view of a vapor deposition apparatus. It is a figure which shows the vapor deposition process by the manufacturing method of the organic electroluminescence display of one Embodiment of this invention. It is a figure which shows the state on which the organic layer was laminated | stacked by the manufacturing method of the organic electroluminescence display of one Embodiment of this invention. It is explanatory drawing at the time of vapor-depositing the conventional organic layer.

Next, the deposition mask and the deposition method of the first and second embodiments of the present invention will be described with reference to the drawings. As a plan view of the vapor deposition mask 1, a cross-sectional view taken along line IB-IB in FIG. 1A, a part of a C view of FIG. 1A, and a part of a D view of FIG. The vapor deposition mask 1 according to the embodiment includes the mask body 10 in which the opening pattern 11 a is formed, and the frame 15 in which at least a part of the peripheral portion of the mask body 10 is bonded to hold the mask body 10 in a constant state. doing. In FIG. 1A, a part of the mask main body 10 is broken to expose the frame 15 and the face plate 152 of the exposed frame 15 is removed, whereby the state of the core portion 151 (the direction of the through hole (air gap 151a)) is obtained. It is shown to be understood.

As shown in FIGS. 1C and 1D, the frame 15 is a basic structure formed on a sandwich structure 150 in which a face plate 152 is attached to the opposing surface of at least a part of the core 151 containing the air gap 151a. At least a part of the frame 15 is formed by a columnar body formed by laminating unit structures 155 having a sandwich structure via the connecting face plate 153. The unit structure means a sandwich structure 150 of one layer to be stacked regardless of the number of the voids 151a.

The mask body 10 may be a hybrid type in which a metal support layer 12 having an opening 12 a formed so as not to close the opening pattern 11 a of the resin film 11 is attached to the resin film 11, for example, a thickness of about 30 μm The metal mask may have a tapered opening pattern formed of only metal foils (thin plates) such as invars, or a resin made of only the resin film 11 formed of polyimide or the like without the metal support layer 12 being attached. It may be a film mask. In the case of a hybrid mask, the metal support layer 12 is bonded to the frame 15 together with the resin film 11.

As described above, in the conventional vapor deposition mask, the temperature of the vapor deposition mask 1 and the vapor deposition substrate 2 (see FIG. 6) around the frame 15 is likely to rise, and the weight of the vapor deposition mask 1 is very large with the enlargement. The problem is that there is a limit to enlargement. That is, as described later, at the time of vapor deposition, the vapor deposition material is scattered toward the vapor deposition mask 1 from the vapor deposition source 5 (see FIG. 6). Therefore, the deposition source 5 has a very high temperature, and the portion of the frame 15 closest to the deposition source 5 also has a temperature rise due to radiant heat. In the deposition mask 1, the temperature of the metal support layer 12 or the portion of the mask main body 10 consisting of the metal mask naturally also rises, and the heat is transferred to the deposition substrate 2. However, as described above, the temperature rise of the portion of the frame 15 is larger than the temperature rise of the metal support layer 12 in the central portion, and furthermore, the heat capacity is also large because of the weight. Further, although invar having a small coefficient of linear expansion has a relatively low thermal conductivity of 13 W / (m · K) among metals, it is still 1 to 2 orders of magnitude higher than glass or acrylic. Therefore, it is considered that the heat conduction to the vapor deposition target substrate 2 by the frame 15 is larger than the heat transmitted to the vapor deposition target substrate 2 from the central portion of the mask main body 10 such as the metal support layer 12. Moreover, since the conventional frame 15 is formed of a solid bar, once the temperature rises, the heat capacity is large, so the high temperature is maintained for a long time. Therefore, when vapor deposition on the vapor deposition substrate 2 is completed, the vapor deposition substrate 2 is replaced, and another vapor deposition substrate 2 is deposited, the temperature of the frame 15 is high from the beginning, and the vapor deposition substrate 2 in the vicinity thereof is The temperature tends to rise from the time of wearing. Therefore, the vapor deposition substrate 2 has a problem that thermal expansion at the peripheral portion is large, and positional deviation easily occurs with the central portion.

Also, as the deposition mask becomes larger, the weight of the frame 15 of the structure shown in FIG. 1A also becomes an issue. That is, as described above, the mask main body 10 including the resin film 11 and the metal supporting layer 12 is bonded to the frame 15, but the mask main body 10 is tensioned from the viewpoint of the stability of the shape of the opening. And attached to the frame 15. This tension is, for example, about 10 N per one strip-like resin film 11 shown in FIG. 1A, and the width and thickness of the frame 15 are each required to be about several tens of mm. Even when the mask main body 10 is made of a metal film, a tension larger than that of the resin film 11 is applied from the viewpoint of preventing warpage, bending, and the like. In the case of the mask main body 10 composed of the resin film 11 and the metal support layer 12, for example, when the evaporation mask 1 of G6H size described above is formed of a 50 mm × 40 mm bar, the size of G6 H is the size of the substrate Since the frame 15 is disposed on the outer periphery thereof, the length of each side of the frame 15 is 50 mm longer than the size of G6H. Since the frame 15 has a rectangular frame shape, for example, as shown in FIG. 1A, the length of only the two long side vertical frames 15a is increased to make the short side horizontal frames 15b the size of the substrate size. In this case, since it is necessary to make the longitudinal frame 15a of the long side twice as long as the frame width (about 100 mm), it becomes the same as extending each side by 50 mm.

Therefore, the total volume of the frame 15 is 2 × (1550 mm + 950 mm) × 2000 mm ² = 10,000 cm ³ . As described above, the material of the frame 15 is preferably close to the linear expansion coefficient of the vapor-deposited substrate 2 (see FIG. 6), and glass as the vapor-deposited substrate 2 or polyimide having a linear expansion coefficient close to glass is used. Therefore, Invar is generally used as the metal support layer 12 or the frame 15 of the deposition mask 1. Since the specific gravity of Invar is about 8, its weight is about 80 kg. Since the purpose is to make the size larger than G6H, not only the sides of the frame 15 become longer, but the width and thickness of the frame 15 also need to be increased, and the weight becomes even heavier than this weight. As a result, transport by the robot arm becomes impossible.

As a result of intensive studies to solve such problems, the inventor of the present invention has made a sandwich structure having an air gap, thereby using the same material as in the prior art while maintaining the same coefficient of linear expansion, mechanical strength. It has been found that the weight can be significantly reduced. In particular, it has been found that no problem occurs even when the mask main body 10 is tensioned and joined to the frame 15 with almost no loss of mechanical strength by forming the void portion into a honeycomb structure. Further, by using carbon fiber reinforced plastic (CFRP), the linear expansion coefficient can be made almost the same as that of the conventional invar, mechanical strength such as rigidity is also strong, and specific gravity is about 1/4 to 1/5 of invar The inventors have found that it can be made smaller. By using this material to make the aforementioned sandwich structure, the weight can be further reduced to 1/4 or less, and eventually, the weight can be reduced to about 1/20 of pure invar and mechanical strength is also sufficiently obtained. It was done.

Here, carbon fiber reinforced plastic (CFRP) is a composite material of reinforced fiber such as carbon fiber and plastic (resin), so that carbon fiber can exhibit the characteristics of the strong, light and thin material. It is Carbon fibers include carbon fibers in a broad sense including various fiber materials having high-strength carbon fibers, high-rigidity carbon fibers, glass fibers, silicon carbide (SiC) and the like as reinforcing fibers, in addition to ordinary carbon fibers in a narrow sense. By changing the type of reinforcing fiber (carbon, SiC, etc.), it is possible to adjust the values of linear expansion coefficient and thermal conductivity, in addition to tensile strength, tensile modulus, flexural strength and flexural modulus. Among them, SiCFRP, in which silicon carbide is a reinforcing fiber, is suitable as a mask frame because its linear expansion coefficient is close to that of polyimide.

If it is a sandwich structure incorporating the air gap 151a (see FIG. 1C), as described later, it is not only very strong against the stress applied in the axial direction of the air gap (through hole) 151a, but also perpendicular to the axis Strong against stress in the direction. However, the stress in the direction perpendicular to the axis is less resistant than the stress in the axial direction. On the other hand, as shown in FIG. 1A, since the strip-like mask main body 10 is tensioned and attached to the vertical frame 15a by welding or the like, the vertical frame 15a is strongly pulled in the direction of the frame 15. Therefore, in the vertical frame 15a, it is preferable that the through holes 151a be formed in the direction from the inside to the outside of the frame 15.

On the other hand, since the horizontal frame 15b is also sandwiched by the two vertical frames 15a, it is desirable that the horizontal frame 15b be resistant to stress in the vertical direction with the two vertical frames 15a. However, even the horizontal frame 15b has a length of about 900 mm or more, and it is difficult to make a sandwich structure having a through hole 151a of this length by itself, and even if it is made, the buckling strength is reduced. Can not withstand the compression force of the vertical frame 15a. Therefore, as a result of intensive investigations by the inventor of the present invention, for example, a unit structure 155 of sandwich structure having a height of about 10 to 100 mm, preferably about 30 to 80 mm is formed. By laminating through 153, a very rigid columnar body could be formed. The connecting face plate 153 may be the same as the face plate 152 of the sandwich structure 150, but a thinner metal plate of about 2 to 10 mm thickness or a plate made of CFRP as described above may be used.

The unit structural body 155 does not mean, for example, a portion of a honeycomb structure of one hole when the sandwich structural body 150 is formed in a honeycomb structure, but means a unit of the sandwich structural body to be laminated. . Therefore, for example, as shown in FIG. 2B, in the case where the sandwich structure formed in a plane is laminated in a plane, the one layer becomes a unit structure, and the laminated sandwich structure is cut. When it is formed into a columnar shape, the sandwich structure of one layer corresponding to the cross-sectional area of the rod becomes a unit structure.

That is, the horizontal frame 15 b shown in FIG. 1A is formed of a sandwich structure 150 formed in a columnar shape by laminating such unit structures 155. As a method of forming such a laminate, for example, as shown in FIG. 2A, it is a box shape having a hollow rectangular cylinder with one surface cut away, and a sandwich structure in a first face plate 152a having a U-shaped cross section. The unit structure 155 may be overlapped and inserted, and then the U-shaped opening surface may be covered with the second face plate 152b.

In this case, the unit structural members 155 may be joined or not joined together, and both end faces of the laminated structure may be joined by the face plate 152 without a gap. When bonded, the overall dimensions are likely to vary depending on the thickness of the bonding material such as the adhesive or the brazing material, but such problems do not occur if only overlapping is performed, and the laminate can be obtained with the correct dimensions. . In the case of bonding, the connection face plate 153 may not be formed in each unit structure 155, and one connection face plate 153 may be formed between adjacent unit structures 155.

Further, as shown in FIG. 2B, a plurality of layers of one layer of honeycomb structure (one without the face plate 152 of the sandwich structure 150) is laminated and bonded by an adhesive or the like, and cut by a necessary width. It can also be made columnar. Also in this case, the sandwich structure 150 having the face plates 152 on both sides can be stacked as the unit structure 155. In this case, after cutting to a desired columnar cross-sectional area, it is also possible to overlap and join by welding or the like at the end face of the periphery.

The example shown in FIG. 2B is stacked so that the positions of the through holes 151a of the honeycomb structure coincide with each other. For example, as shown in the plan view of FIG. 2C, the through holes 151a in the first and second layers are laminated. Position of the second layer (upper layer or lower layer of the first layer) comes to a connection point of the honeycomb structure of the second layer (upper layer or lower layer of the first layer) (consolidated point of the thin portions 151b). It is also possible to overlap. With such a laminated structure, the stress applied in the direction perpendicular to the surface is further enhanced, and the stress applied in the lateral direction is also enhanced.

An example of a method of manufacturing such a one-layer honeycomb structure sandwich structure 150 will be described. The core portion 151 of the sandwich structure 150 having a honeycomb structure may be formed of a plate-like body 17 as shown, for example, in FIGS. 3A to 3D. That is, as shown in FIG. 3A, when the thickness d is about 0.5 mm, the width h (the height of one layer shown in FIG. 2B or the core portion 151 of the honeycomb structure of the vertical frame 15a of FIG. An adhesive layer 18 with a width w of about 2.5 mm to 5 mm is spaced by 3 w on one invar plate (plate-like body 17) having a height h (see FIG. 1B) of about 20 mm to 50 mm. The adhesive layer 18 is formed on the second plate-like body 17 with a width of w from the position of the end of the first adhesive layer 18 at an interval of 3 w. Next, an adhesive layer 18 having a width w is similarly formed on the third plate-like member 17 from the position at the end of the second adhesive layer 18 with a space of 3 w. Similarly for the fourth sheet, the width of the third sheet-like member 17 to w is shifted to form an adhesive layer 18 with an interval of 3 w. The adhesive layer 18 is formed so that the fifth plate-like member 17 is at the same position as the first plate-like member 17, and the adhesive layer 18 is similarly applied to the sixth and subsequent plate-like members 17. Form. After the required number of plate-like members 17 are formed, they are superposed and bonded (see FIG. 3B). As the adhesive, for example, a polyimide-based adhesive can be used. Alternatively, it may be brazed with silver wax or the like.

Thereafter, by gripping and stretching the bottom and top plate members 17, as shown in FIG. 3C, the peripheries of the portions bonded with the adhesive layer 18 are respectively the portion bonded and the portion bonded The portion which is deformed so as to form an angle of 120 ° and which is adhered is a thickness of 2 d thick, and the other portion is a thin portion 151 b of thickness d, and a core portion 151 having an air gap 151 a is formed . In this example, the cell size c is formed to be about 5 mm to 10 mm. A perspective view of this condition is shown in FIG. 3D. A cross section of a length (a width of the frame 15) s (see FIG. 1C) obtained by adding a width t of the core portion 151 of FIG. 3C and twice a thickness of the face plate 152 described later A columnar body is formed. The width s and the height h are each formed to be about several tens of mm, and the length is set according to the size of the vapor deposition mask 1. However, this is only an example, and these dimensions can be arbitrarily set depending on which direction the through holes are in the frame 15.

Thickness d of plate-like object 17 used in the above-mentioned example is not limited to this, either, It chooses to a thickness which can endure a required load. For example, in order to withstand a large load, the plate thickness d may be increased. In this case, if the plate material becomes too thick, it becomes difficult to deform when pulling and stretching the plate-like members on the upper surface and the lower surface, so it is possible to form a groove that makes it easy to bend in the portion to be bent.

The sandwich structure 150 having a honeycomb structure is characterized by being strong against in-plane / out-of-plane shear loads and out-of-plane compressive loads and having high out-of-plane rigidity (high buckling strength). By applying stress in the direction of the maximum strength, the merit (light weight and high rigidity) of the honeycomb structure is utilized. The rigidity is higher as the value of 2d / c is larger using the thickness d shown in FIG. 3A and the cell size c shown in FIG. 3C. Therefore, to increase the rigidity, the plate thickness d should be large. The desired rigidity can be easily obtained by reducing the cell size c.

The core 151 thus formed can be used as a rigid material even as it is, but when it is used in this one layer, as shown in FIG. 1C, the periphery is surrounded by a face plate 152 to form a sandwich. The structure 150 can further increase the rigidity. The face plate 152 is, for example, an invar plate having a thickness of about 3 mm. In FIG. 1C, the face plate 152 closing the air gap (through hole) 151a is not shown in order to make the internal structure intelligible. The face plate 152 may be attached to each side of a quadrangular prism, but as shown in FIG. 2A described above, it may be attached by bending so as to surround four sides with one or two plate materials. Strong against stiffness in all directions. When using as the flame | frame 15 of the vapor deposition mask 1, it is preferable not only from the point of rigidity but from a viewpoint of suppressing that an organic material etc. penetrate | invade in the space | gap 151a. This point is the same as in the case where the above-described unit structures 155 are stacked to form a columnar body. That is, at the time of vapor deposition, the organic material floats in the vacuum chamber and easily enters the air gap 151a. In addition, when a certain number of depositions are performed, the deposition mask 1 needs to remove the organic material attached to the deposition mask 1, and the deposition mask 1 is periodically cleaned. During the cleaning, the cleaning solution also enters the air gap 151a, and may remain in the air gap 151a even after the cleaning. The vapor deposition mask 1 is placed in a vacuum chamber and vapor deposition is performed. Therefore, if the cleaning liquid remains in the air gap when vacuumed, it becomes an impurity contamination source (gas generation source) and normal vapor deposition can not be performed.

Therefore, the gap 151 a is preferably sealed by the face plate 152. Not only the opening surface of the air gap (through hole) 151a but also the side surface (side surface parallel to the through hole 152) have unevenness, it is preferable that the face plate 152 be attached for the same reason. The attachment of the face plate 152 can be formed by an adhesive, brazing or the like when forming the core portion 151 of the honeycomb structure described above. In the upper and lower surfaces shown in FIG. 3C, the core plate 151 can be firmly connected with the portion where the surface plate 152 can adhere to the surface portion of the core 151, but in the left and right surfaces of FIG. Since the contact area with the face plate 152 is small, a sufficient adhesive and brazing material are required. However, as described above, the face plate 152 is not attached separately on each side, and by bending and attaching one metal plate, it is also resistant to stress, and the adhesive strength with the core portion 151 is also obtained. Become stronger. As a result, as described above, it is preferable that all six sides of the quadrangular prism be surrounded by the face plate 152.

In this example, the core portion 151 is formed from the plate-like body 17, but the formation of the core portion 151 is not limited to this example. For example, it can also be manufactured by forming a through-hole in a solid metal material, and can also be formed by die molding. In particular, in the case of CFRP described above, since it is hard to deform, it is formed by injection molding. According to such a method, since it is not necessary to bond the plate-like members 17, by bonding two thin portions 151b, there is no part having a thickness of 2 d, and a constant thickness can be obtained. An example of this is shown in FIG. 3E. FIG. 2C shows the thin portion 151b in the example of a constant thickness for simplification.

In the case of CFRP, although mainly formed by injection molding, CFRP has anisotropy, and mechanical strength differs depending on the direction, amount, position, etc. of carbon fiber to increase mechanical strength in a specific direction. be able to. That is, generally, as shown in FIG. 3F, in the injection molded product, the molten resin flows in the mold, and the direction of the filler 172 is aligned in a certain direction in the resin 171, and the mechanical is high in that direction. Strength is obtained. Thus, in particular, the direction in which stress is applied can be this direction. In this case, the buckling stress is further strengthened by injection molding so that the filler of the carbon fiber described above is oriented in the direction of the through hole 151a. In the case of manufacturing a laminate by CFRP, the connecting face plate 153 can also be formed of CFRP, and the face plate 152 having a sandwich structure can also use CFRP, and the outer surface of the core portion 151 is electroless plated and electrolytic By providing a metal film by plating, vacuum evaporation, sputtering or the like, welding or the like is also possible.

In the example described above, the example of the narrow sense honeycomb structure of regular hexagon has been described, but the shape of the air gap 151a is not necessarily limited to the regular hexagon, and it is somewhat weak against lateral stress. It may be a broken hexagon, a polygon other than a hexagon, or a circle in an extreme case. In the case of a circular shape, by making a circular hole with a small radius inscribed in a region surrounded by four circles, a thin walled portion 151b having a large number of air gaps 151a can be formed similarly. In the present specification, a broad honeycomb structure including these structures is called a honeycomb structure. Furthermore, in the present embodiment, not only in such a honeycomb structure but also in a corrugated structure shown in FIGS. 4A to 4B, the axial direction of the through hole (air gap) 161a is directed in the stress application direction. Similarly, a lightweight and mechanically strong frame 15 is formed.

The structure shown in FIG. 4A is a sandwich by forming a corrugated plate 161b by bending a plate-like body into a wave plate to form a core portion 161 together with an air gap 161a and pasting a face plate 162 outside the peaks and valleys thereof. A structure 16 is formed. In this structure, the force in the horizontal direction in FIG. 4A (x-axis direction in FIG. 4A) is somewhat weak, but the stress in the axial direction (y-axis direction in FIG. 4A) is strong. Some degree of resistance to stress in the direction. In this case, as shown in FIG. 4B, by strongly bonding the corrugated plate 161b and the face plate 162, a large mechanical strength can be obtained. Therefore, it is preferable to flatten the corrugated peaks and valleys 161b1 of the corrugated plate 161b to a certain extent and bond them with the adhesive 163 or a brazing material. In the example shown in FIG. 4A, the face plate 162 is provided only on the upper and lower surfaces, but it is preferable that the periphery of the side is also covered with the face plate 162.

(Structure of vapor deposition mask)
The vapor deposition mask 1 of the present embodiment is characterized by the structure of the frame 15 that holds the mask body 10. Specifically, as shown in FIG. 1C with face plate 152 of arrow C in FIG. 1A removed, and with face plate 152 removed in arrow D of FIG. 1A in FIG. 1D, frame 15 penetrates. A hole (air gap) 151a is formed, and the through hole 151a is formed in a hexagonal shape. By being formed in such a hexagonal honeycomb structure, not only the stress in the axial direction of the through hole 151a but also the stress in the direction perpendicular to the opening surface of the through hole 151a is very strong. The reason is that, for example, as a schematic view of the honeycomb structure is shown in FIG. 5, when a stress P in the lateral direction is applied to the through hole 151a, the stress is equally shared to each side of the hexagon. Therefore, it is very strong against the lateral stress P, and the stress per unit mass can be four to six times stronger than that of the solid material. Conversely, in order to maintain the same stress, the weight can be reduced to about 1/4 to 1/6.

However, in the present embodiment, while the direction in which the strong stress is applied is not the lateral direction of the honeycomb structure but the axial direction that can best withstand the stress, the sandwich structure is used so as not to buckle even in a long rod shape. It is characterized in that unit structures 155 are stacked. As shown in FIG. 1A, since the vertical frame 15a is attached by applying tension to the mask body 10, the through holes 151a extend from the inside of the frame 15 to the outside so that the tension can be countered. The formed sandwich structure 150 is used.

On the other hand, since the mask body 10 is not attached to the lateral frame 15b, direct stress is not applied. Therefore, in the case of a vertical vapor deposition apparatus (when the vertical frame 15a is parallel to the vertical direction), in the direction from the inside of the frame 15 to the outside, as in the vertical frame 15a, it can bear its own weight. A structure having a through hole is assumed. However, since the vertical frame 15a is pulled by the mask body 10, eventually the two vertical frames 15a are pulled to each other. As a result, the lateral frame 15b has to withstand its compressive force. Therefore, a columnar frame formed of a stack of unit structures described above is used for the horizontal frame 15b. The stress applied in the axial direction of the columnar body in which the unit structures 155 are stacked can be temporarily reset and accumulated by the connecting face plate 153 by using the stacked body of the unit structures 155 having such large rigidity. It disappears. As a result, the buckling strength can also be significantly improved.

Further, in such a structure, in the case of forming a vertical vapor deposition apparatus, if the vertical frame 15a is erected vertically (horizontally extended), the structure of the frame 15 is the same as that of the vertical frame 15a. Both have a structure that is strong against the stress in the direction of gravity, so that it is also robust against vertical evaporation equipment. In this case, since the vertical frame 15a (longer frame) is erected up and down, the occupied area of the vapor deposition apparatus is slightly larger than when the vertical frame 15a is vertical, for example, the difference between 900 mm and 1500 mm with G6H. There is not a big difference by itself, but it has the merit that it is easy to work stably in landscape rather than portrait. Compared to a horizontal vapor deposition apparatus (a deposition mask or an apparatus for placing a deposition substrate in parallel with a horizontal surface), the occupied area is greatly reduced, and particularly in the manufacture of an organic EL display device, several vacuum chambers are arranged side by side. Since deposition is performed while moving the deposition substrate 2, the effect of reducing the occupied area is very large.

By making the sandwich structure 150 having such an air gap 151a, even if the material is the same as the conventional frame 15, the weight can be reduced to about 1/4 to 1/6, and a portion of the thin portion 151b The heat capacity is also reduced because the volume of Moreover, if the same material is used, physical constants such as the linear expansion coefficient and the thermal conductivity do not change. Rather, heat conduction can be greatly reduced by the presence of air gaps (through holes 151a).

The columnar sandwich structure 150 thus formed is used as the vertical frame 15 a on the long side of the deposition mask 1, in which the through holes 151 a are directed out of the frame of the frame 15. As the horizontal frame 15b, one formed into a columnar shape by laminating the unit structure body 155 having the sandwich structure described above is used. And two each are prepared according to the length of each side of the frame 15, and the frame of the frame 15 is manufactured by joining at an end. Bonding of the columnar sandwich structure 150 is conventionally performed by using a bolt or the like. However, in the present embodiment, sufficient fixing is required so that a large number of voids do not occur and twisting or the like occurs. Therefore, it is preferable to place a splint or the like on the corner of the frame-like square, penetrate the sandwich structure 150, and tighten and assemble with a bolt and a nut. Bonding of the corner portions is sufficiently performed, and twisting and the like hardly occur.

There are various methods for attaching the mask main body 10 to the frame 15, for example, the mask main body 10 is pulled along the short side horizontal frame 15 b of the rectangular frame 15 and welded to the long side vertical frame 15 a And so on. In the example shown in FIG. 1A, although only five strip-shaped mask bodies 10 are shown, there is also an example in which, for example, about 12 sheets are actually attached sequentially, in that case, a stress of about 10 N per sheet The stress of about 120 N is applied overall. Therefore, as described above, the vertical frame 15a and the horizontal frame 15b are formed. As described above, the mask main body 10 is a mask of a single metal, a mask of a single resin film, or a hybrid mask using both of them. However, the mask main body 10 consisting only of a resin film is directly bonded by an adhesive or the like It is also good. In this case, an adhesive that does not generate a gas during deposition is used. For example, as the adhesive, a complete curing adhesive such as a thermosetting epoxy resin or a polyimide resin is preferable.

When welding the strip-like mask main body 10 to the frame 15, the end of the mask main body 10 is lengthened, and it is joined to the side surface of the frame 15 (the outer peripheral wall which is the side opposite to the inside of the frame 15) Is more rigid against stress due to tension. In this case, welding is performed from the side of the frame 15. In particular, the effect is large when the mask main body 10 made of only a resin film is attached with an adhesive.

As described above, it is preferable that the air gap 151a be closed by the face plate 152, but when closing the air gap 151a, the inside of the air gap 151a is made negative pressure (decompression) by attaching the face plate 152 under reduced pressure. Is more preferable. As described above, since the deposition mask 1 is used in a vacuum deposition apparatus, if the inside of the air gap 151a is sealed at 1 atm, leakage of air trapped in the air gap 151a can occur in the vacuum chamber. It is because it will reduce the degree of vacuum in the vacuum chamber. Further, if the negative pressure is applied, the heat conduction is also reduced, and the heat conduction of the frame 15 heated by the vapor deposition source 5 (see FIG. 6) can be further suppressed.

From the viewpoint of suppression of heat conduction, heat conduction can be further suppressed by sealing a rare gas such as argon in the air gap 151a. The noble gas has a low thermal conductivity. In order to reduce the pressure in the air gap 151a or to enclose a rare gas, the core portion 151 and the face plate 152 may be bonded in a reduced pressure atmosphere and / or a rare gas atmosphere.

The sandwich structure 150 having such an air gap 151a is particularly strong against the load in the direction parallel to the axis of the air gap 151a. On the other hand, as described above, in order to stabilize the opening 11a of the resin film 11 firmly, the vapor deposition mask 1 tensioned by pulling the mask main body 10 (see FIG. 1B) composed of the resin film 11 and the metal support layer 12 It is joined to the frame 15 in the state.

The mask body 10 of the vapor deposition mask 1 is provided with a resin film 11 and a metal support layer 12 as shown in FIG. 1B as a cross-sectional view of an example of a hybrid mask, and a magnetic material is used for the metal support layer 12. As the metal support layer 12, for example, Fe, Co, Ni, Mn or an alloy of these may be used. Among them, Invar (an alloy of Fe and Ni) is particularly preferable because the difference in linear expansion coefficient with the vapor deposition substrate 2 is small, and there is almost no expansion due to heat. The thickness of the metal support layer 12 is about 5 μm to 30 μm.

In FIG. 1B, the opening 11a of the resin film 11 and the opening 12a of the metal supporting layer 12 are tapered so as to be tapered toward the deposition target substrate 2 (see FIG. 6). The reason is that when the vapor deposition material 51 (see FIG. 6) is vapor deposited, it does not become a shadow of the scattered vapor deposition material 51. The mask body 10 is not limited to the hybrid mask, and may be a metal mask or a mask of only a resin film.

When the mask main body 10 is a metal mask, for example, an invar sheet having a thickness of about 30 μm is used to form the opening pattern. The opening pattern is formed in a tapered shape in which the deposition substrate side is tapered, as in the case of the resin mask, by adjusting the conditions of the etching process. For example, as shown in FIG. 1A, a plurality of such mask bodies may be attached in a strip shape, or may be attached in a single sheet. This metal mask is also attached to the frame by welding or the like under tension. A metal mask is harder than a resin film, and it is more likely to warp or bend, so it needs to be tensioned more than a resin mask, but since the frame of this embodiment is very rigid, it is more preferable than a resin film mask. Also when the frame of this embodiment is used for a metal mask, the effect is large.

The vapor deposition mask 1 is obtained by attaching such a mask main body 10 to the above-described frame-shaped frame 15. The vapor deposition mask 1 has a structure in which the metal support layer 12 is attached to the resin film 11, but the metal support layer 12 may be omitted. In the absence of the metal support layer 12, the resin film 11 is required to be more stable, and therefore, needs to be fixed to a firm and robust frame 15. As a result, the frame 15 tends to be heavy, but the sandwich structure 150 having the air gap 151a can prevent its weight from increasing. When the metal support layer 12 is not provided, the magnet 15 can be adsorbed by using a magnetic material for the frame 15 of the deposition mask 1.

By making the frame 15 of the vapor deposition mask 1 into a sandwich structure 150 having such an air gap 151a, the weight becomes very light. That is, by making the honeycomb structure of the structure shown in FIG. 3D described above, the weight of the vapor deposition mask 1 of G4.5 is reduced to about 1/4 to 1/6 as compared to the conventional pure case. There was no problem in the stress caused by the attachment of the main body 10. As a result, even if the vapor deposition mask 1 is about 3 to 4 times heavier than this, that is, about G8 (about 2200 mm × 2400 mm), the robot arm can sufficiently carry it. Even if transfer by robot arm becomes possible, space is required in the horizontal vapor deposition apparatus, and particularly in the manufacture of organic EL display devices, approximately 6 to 10 vacuum chambers are arranged and the deposition substrates 2 are sequentially Because the deposition is carried out by replacement, a very large space is required. Therefore, it is necessary to use a vertical vapor deposition apparatus (with the vapor deposition mask 1 and the vapor deposition substrate 2 standing up and scattering the vapor deposition material from the side) to reduce the area of the factory site.

Further, in the deposition mask according to the present embodiment, the frame 15 has a large number of voids 151a. Therefore, heat conduction is greatly suppressed. That is, the surface opposite to the surface to which the mask main body 10 of the frame 15 is attached faces the deposition source 5 and the temperature is very likely to rise. However, heat conduction can be significantly suppressed by forming a large number of air gaps 151a. Since air or decompressed air, a rare gas or the like further reduces the heat conduction, the temperature rise of the mask main body 10 or the vapor deposition substrate 2 can be suppressed. As a result, temperature distribution of the vapor deposition mask 1 and the vapor deposition substrate 2 is less likely to occur. This can form a finer pattern of the organic layer.

According to the vapor deposition mask 1 of the present embodiment, the heat capacity is reduced because the weight of the frame 15 is significantly reduced. Therefore, the temperature is likely to rise, but is likely to fall. That is, even when the deposition target substrate 2 is replaced and organic materials are continuously deposited on a large number of deposition target substrates 2, heat is accumulated in the deposition mask 1 and the next deposition target substrate 2 is disposed and heated immediately. It does not happen. As a result, stable deposition can be repeated.

(Schematic configuration of vapor deposition apparatus)
In a vapor deposition apparatus using the vapor deposition mask 1 according to an embodiment of the present invention, as shown in FIG. 6, a mask holder is disposed so that the vapor deposition mask 1 and the vapor deposition substrate 2 are disposed close to each other inside a vacuum chamber. A substrate 19 and a substrate holder 29 are provided so as to move up and down. The substrate holder 29 is connected to a driving device (not shown) so that the peripheral portion of the deposition target substrate 2 can be held by a plurality of hook-like arms and can be vertically moved up and down. In the case of replacing the deposition target substrate 2 etc., the robot arm receives the deposition target substrate 2 carried into the vacuum chamber with a hook-like arm, and the substrate holder 29 continues until the deposition target substrate 2 approaches the deposition mask 1. Go down. An imaging device (not shown) is also provided so that alignment can be performed. The touch plate 4 is supported by the support frame 41, and is connected to the drive device that lowers the touch plate 4 to be in contact with the deposition substrate 2 via the support frame 41. The deposition substrate 2 is flattened by lowering the touch plate 4.

The deposition apparatus captures an alignment mark formed on each of the deposition mask 1 and the deposition target substrate 2 at the time of aligning the deposition mask 1 of the first embodiment with the deposition target substrate 2. The micromotion device is also provided to move the relative to the vapor deposition mask 1. The alignment is performed in a state where the energization of the electromagnet 3 is stopped so that the deposition mask 1 is not attracted unnecessarily by the electromagnet 3. Thereafter, the electromagnet 3 held by the touch plate 4 and the similar holder (not shown) is lowered and a current flows, whereby the deposition mask 1 is attracted toward the deposition target substrate 2.

In this embodiment, the frame 15 of the vapor deposition mask 1 has a structure in which the core portion 151 of the sandwich structure 150 having an air gap is sandwiched between the face plates 152. Therefore, even when the robot arm (not shown) It can be done.

In the electromagnet 3, a plurality of unit electromagnets in which a coil 32 is wound around a core 31 are fixed by a coating 33 made of resin or the like. In the example shown in FIG. 6, a plurality of unit electromagnets are connected in series, with the terminals 32a to 32e of the coil 32 of each unit electromagnet formed. However, the configuration of the electromagnet 3 is not limited to this example, and may be variously configured. The shape of the core 31 may be square or circular. For example, when the size of the vapor deposition mask 1 is about G6 (1500 mm × 1800 mm), the unit electromagnet shown in FIG. 1 has a core 31 whose cross section has a size of about 50 mm square is shown in FIG. As shown, it may be arranged in a plurality according to the size of the deposition mask 1 (in FIG. 6, the horizontal direction is scaled and the number of unit electromagnets is drawn small). In the example shown in FIG. 6, the coils 32 are connected in series. However, the coils 32 of the respective unit electromagnets may be connected in parallel. Also, several units may be connected in series. The current may be applied independently to a part of the unit electromagnet.

The vapor deposition mask 1 is provided with a resin film 11 and a metal support layer 12 and a frame (frame) 15 formed around the resin film 11 as shown in FIG. 1B described above, and the vapor deposition mask 1 is shown in FIG. As shown, the frame 15 is mounted on the mask holder 19. By using a magnetic material for the metal support layer 12 and / or the frame 15, a suction force is exerted between the metal support layer 12 and / or the frame 31 with the core 31 of the electromagnet 3 to be attracted across the deposition target substrate 2.

In addition, as the deposition source 5, various deposition sources, such as point shape, linear shape, and planar shape, may be used. For example, the entire surface of the vapor deposition substrate 2 can be obtained by scanning a line type vapor deposition source 5 (extending in a direction perpendicular to the paper surface of FIG. 6) in which crucibles are linearly arranged. Deposition is performed. Therefore, the vapor deposition material 51 is scattered from various directions, and the

openings

11a and 12a described above are tapered so that the vapor deposition material 51 coming from an oblique direction can reach the vapor deposition substrate 2 without being blocked. It is formed.

(Deposition method)
Next, a vapor deposition method according to a second embodiment of the present invention will be described. In the vapor deposition method of the second embodiment of the present invention, as shown in FIG. 6 described above, disposing the vapor deposition substrate 2 and, for example, the vapor deposition mask 1 shown in FIG. And depositing the deposition material on the deposition target substrate 2 by scattering of the deposition material from the deposition source 5 disposed apart from the deposition mask 1. That is, the frame 15 of the vapor deposition mask 1 is formed by the sandwich structure 150 in which the core portion 151 having the air gap 151a and the thin portion 151b is covered with the face plate 152 like a honeycomb structure in the frame 15 of the vapor deposition mask 1 There is.

Specifically, as described above, the deposition substrate 2 is superimposed on the deposition mask 1. The alignment between the deposition substrate 2 and the deposition mask 1 is performed as follows. The deposition target substrate 2 is moved relative to the deposition mask 1 while observing alignment marks for alignment formed on the deposition target substrate 2 and the deposition mask 1 with an imaging device. By this, the opening 11a of the vapor deposition mask 1 and the vapor deposition place of the vapor deposition substrate 2 (for example, in the case of the organic EL display described later, the pattern of the first electrode 22 of the support substrate 21) can be matched. After alignment, the electromagnet 3 is operated. As a result, a strong attractive force is exerted between the electromagnet 3 and the vapor deposition mask 1 so that the vapor deposition substrate 2 and the vapor deposition mask 1 come close to each other.

Thereafter, as shown in FIG. 6, the deposition material 51 is deposited on the deposition target substrate 2 by the scattering (vaporization or sublimation) of the deposition material 51 from the deposition source 5 disposed apart from the deposition mask 1. Specifically, as described above, although a crucible or the like or a line source formed in line is used, it is not limited thereto.

According to this vapor deposition method, since the vapor deposition mask 1 is lightweight, mounting of the vapor deposition mask 1 in a vacuum chamber becomes very easy. In addition, since the weight is reduced, the transfer by the robot arm is facilitated, and the deposition mask 1 can be further enlarged. That is, mass production is possible and cost reduction can be achieved. Furthermore, since the heat conduction is suppressed by the air gap 151a of the frame 15 and the heat capacity is further reduced, the heat is accumulated in the vapor deposition mask 1 and the thermal expansion difference between the vapor deposition substrate 2 and the vapor deposition mask 1 can be suppressed. . As a result, deposition on a large-sized deposition target substrate can be performed, and fine deposition can be performed.

(Manufacturing method of organic EL display)
Next, a method of manufacturing an organic EL display device using the vapor deposition method of the above embodiment will be described. Since manufacturing methods other than the vapor deposition method can be performed by known methods, mainly the method of laminating the organic layer by the vapor deposition method of the present invention will be described with reference to FIGS. 7A to 7B.

In the method of manufacturing the organic EL display device according to the third embodiment of the present invention, a TFT, a flattening film and a first electrode (for example, an anode) 22 (not shown) are formed on a support substrate 21. The vapor deposition mask 1 is aligned and superposed downward, and the vapor deposition material 51 is deposited by forming the laminated film 25 of the organic layer using the vapor deposition method described above. Thereby, the second electrode 26 (for example, a cathode) is formed on the laminated film 25.

For example, although the support substrate 21 such as a glass plate is not completely illustrated, a drive element such as a TFT is formed for each RGB sub-pixel of each pixel, and the first electrode 22 connected to the drive element is flat. It is formed on the passivation film by combining a metal film such as Ag or APC and an ITO film. As shown in FIGS. 7A to 7B, insulating banks 23 made of SiO ₂ or acrylic resin, polyimide resin or the like are formed between the sub-pixels to separate the sub-pixels. The above-mentioned vapor deposition mask 1 is aligned and fixed on the insulating bank 23 of such a support substrate 21. For this fixation, as shown in FIG. 6 described above, for example, adsorption is performed using an electromagnet 3 provided via a touch plate 4 on the surface opposite to the deposition surface of the support substrate 21 (substrate 2 to be deposited). It is done by As described above, since a magnetic material is used for the metal support layer 12 (see FIG. 1B) of the vapor deposition mask 1, when the magnetic field is applied by the electromagnet 3, the metal support layer 12 of the vapor deposition mask 1 is magnetized and the core A suction force is generated between them. Even when the electromagnet 3 does not have the core 31, the electromagnet 3 is attracted by the magnetic field generated by the current flowing through the coil 32.

In this state, as shown in FIG. 7A, the deposition material 51 is scattered from the deposition source (crucible) 5 in the vacuum chamber, and the deposition material 51 is present only on the portion of the support substrate 21 exposed to the opening 11 a of the deposition mask 1. The deposited film 25 of the organic layer is formed on the first electrode 22 of the desired sub-pixel by vapor deposition. The deposition process may be performed on the sub-pixels by sequentially transferring the support substrate 21 to different vacuum chambers. The deposition mask 1 may be used in which the same material is deposited simultaneously on a plurality of sub-pixels. When the vapor deposition mask 1 is replaced, the electromagnet 3 (see FIG. 6) not shown in FIG. 7A is not shown to remove the magnetic field to the metal support layer 12 (see FIG. 1B) of the vapor deposition mask 1. The power supply circuit is turned off.

7A to 7B, the laminated film 25 of the organic layer is simply shown as one layer, but the laminated film 25 of the organic layer may be formed of the laminated film 25 of a plurality of layers made of different materials. For example, as a layer in contact with the anode 22, a hole injection layer made of a material having good ionizing energy consistency that improves the hole injection property may be provided. On this hole injection layer, a hole transport layer capable of confining electrons (energy barrier) to the light emitting layer as well as improving stable transport of holes is formed of, for example, an amine material. Furthermore, a light emitting layer selected according to the light emission wavelength is formed thereon, for example, by doping red or green organic fluorescent material to Alq ₃ for red and green. Moreover, as a blue-based material, a DSA-based organic material is used. On the light emitting layer, an electron transport layer is formed by Alq ₃ or the like, which further improves electron injectability and transports electrons stably. A stacked film 25 of the organic layer is formed by stacking each of these layers by about several tens of nm. An electron injection layer may be provided between the organic layer and the metal electrode to improve the electron injection property of LiF or Liq. In the present embodiment, these are also included in the laminated film 25 of the organic layer.

In the light emitting layer of the laminated film 25 of the organic layer, an organic layer of a material corresponding to each color of RGB is deposited. In addition, it is preferable that the hole transport layer, the electron transport layer, and the like be separately deposited of materials suitable for the light emitting layer, in consideration of light emission performance. However, in consideration of the material cost, the same material may be used in common to two or three colors of RGB. In the case where materials common to two or more sub-pixels are stacked, the deposition mask 1 in which the opening 11 a is formed in the common sub-pixel is formed. In the case where vapor deposition layers differ in individual sub-pixels, for example, each organic layer can be vapor-deposited continuously using one vapor deposition mask 1 in R sub-pixels. In addition, when the organic layer common to RGB is deposited, the organic layer of each sub-pixel is deposited to the lower side of the common layer, and the opening 11a is formed in RGB at the common organic layer. The deposition mask 1 is used to deposit the organic layers of all the pixels at one time. In the case of mass production, a number of vacuum chambers of the vapor deposition apparatus are arranged, and different vapor deposition masks 1 are attached to each, and the support substrate 21 (substrate 2 to be vapor deposited) moves through the respective vapor deposition apparatuses. The deposition may be performed continuously.

As described above, the electromagnet 3 is turned off and the electromagnet 3 is separated from the deposition mask 1 every time the formation of the laminated film 25 of each organic layer including the electron injection layer such as LiF layer is completed. Thereafter, a second electrode (for example, a cathode) 26 is formed on the entire surface. The example shown in FIG. 7B is a top emission type, in which light is emitted from the side opposite to the support substrate 21 in the figure, so the second electrode 26 is made of a translucent material, for example, Mg—Ag of a thin film. It is formed of a eutectic film. Besides, Al or the like may be used. In the case of a bottom emission type in which light is emitted through the support substrate 21, ITO, In ₃ O ₄ or the like is used for the first electrode 22, and the second electrode 26 is a metal having a small work function, For example, Mg, K, Li, Al or the like can be used. A protective film 27 made of, for example, Si ₃ N ₄ or the like is formed on the surface of the second electrode 26. The whole is sealed by a seal layer made of glass, moisture resistant resin film, etc. (not shown), and the laminated film 25 of the organic layer is configured not to absorb moisture. Also, the organic layers can be made as common as possible, and a structure in which a color filter is provided on the surface can be used.

(Summary)
(1) In the vapor deposition mask according to the first embodiment of the present invention, at least a part of the peripheral portion of the mask main body and the mask main body in which the opening pattern is formed are joined to hold the mask main body in a constant state A unit structure of a sandwich structure in which a face plate is attached to an opposing surface of at least a portion of the core portion containing an air gap, through at least a part of the frame via the connecting face plate It is formed in a columnar body by laminating.

According to the vapor deposition mask of the first embodiment of the present invention, while forming the frame of the vapor deposition mask with the sandwich structure having air gaps, even when a large stress is exerted in the axial direction of the frame, the unit structure of the sandwich structure is laminated As a result, the columnar body is formed, so even a very large stress can withstand without buckling. As a result, since the short side which can fully support the compression force by the two long sides to which the mask main body is attached under tension can be obtained, it becomes a light and firm frame.

(2) The through holes are formed by a plurality of through holes in which the air gaps of the unit structure are directed in a certain direction, and the through holes are arranged in the same direction. It is preferable because it has high rigidity against parallel stress.

(3) The core portion of the unit structure may be formed of metal or carbon fiber reinforced plastic. If it is metal, the same material as the frame of the conventional vapor deposition mask can be used, and if it is CFRP, weight is much smaller than Invar, so it is preferable.

(4) It is preferable that the carbon fiber reinforced plastic is a silicon carbide fiber reinforced plastic made of silicon carbide as a reinforced fiber because it has a linear expansion coefficient close to that of the deposition substrate.

(5) The frame has a rectangular shape in the form of a frame, and the air gap is formed from the inside surrounded by the frame to the outside of the frame on the side of the frame to which the mask main body is joined. The side where the mask body is not joined is formed by the columnar body in which the unit structures are laminated, so that the frame on any side of the rectangular frame can be the structure most able to withstand the stress due to the tension of the mask body. So preferred.

(6) The fact that a face plate made of a magnetic metal plate is attached to the entire outer peripheral wall of the frame containing the air gap enables adsorption by a magnetic field regardless of the presence or absence of magnetism in the mask body. preferable.

(7) It is preferable that the heat conduction can be suppressed and the discharge of the gas into the vacuum chamber can be suppressed even when used in the vacuum chamber that the air gap surrounded by the face plate is reduced in pressure. .

(8) It is preferable that the mask main body is a single body of a metal mask or a resin film made of a thin metal plate because the structure is simplified.

(9) The hybrid mask may be a hybrid mask including the resin film having the opening pattern and a metal supporting layer having an opening that is attached to the resin film and does not close the opening pattern. It becomes a stable mask.

(10) A vapor deposition method according to a second embodiment of the present invention includes the steps of: arranging a vapor deposition substrate and the vapor deposition mask according to any one of (1) to (9) above; Depositing the deposition material on the deposition target substrate by scattering of the deposition material from a deposition source placed apart from the deposition mask.

According to the vapor deposition method of the second embodiment of the present invention, even if the mask main body is attached to a pair of opposing frames with tension, the frame inserted between the frames to which the mask main body is attached. Since the axial strength is sufficiently large, the mask body is stably held. As a result, deposition is performed in a fine pattern.

(11) The vapor deposition mask has a frame-like rectangular shape, and the vapor deposition mask is erected such that the frame formed in a columnar shape by crossing the unit structures is erected to intersect a horizontal surface. It is possible to fully support the weight of the mask with the frame while greatly reducing the occupied area of the device (site area).

(12) Further, in the method of manufacturing the organic EL display device according to the third embodiment of the present invention, at least the TFT and the first electrode are formed on the support substrate, and the above (10) or (11) is formed on the support substrate. Forming a laminated film of the organic layer by vapor-depositing the organic material using the vapor deposition method described in 4), and forming a second electrode on the laminated film.

According to the method of manufacturing the organic EL display device of the third embodiment of the present invention, when the organic EL display device is manufactured, since the vapor deposition mask is light, mounting of the vapor deposition mask is easy, and moreover, the vapor deposition mask Also, since the non-uniform thermal expansion of the deposition target substrate is suppressed, the positional deviation between the deposition target substrate and the deposition mask is suppressed, and a display panel with a high definition pattern can be obtained.

DESCRIPTION OF SYMBOLS 1 vapor deposition mask 2 vapor deposition board | substrate 5 vapor deposition source 10 mask main body 11 resin film 11a opening 12 metal support layer 12a opening 15 frame 15a vertical frame 15b horizontal frame 150 sandwich structure 151 core part 151a air gap (through hole)
151b Thin-walled part 152 Face plate 153 Connection face plate 155 Unit structure 21 Support substrate 22 First electrode 23 Insulation bank 25 Laminated film 26 Second electrode

Claims

A mask body having an opening pattern formed thereon,
A frame to which at least a part of the peripheral portion of the mask body is joined to hold the mask body in a fixed state;
At least a part of the frame is formed into a columnar body by laminating a unit structure of a sandwich structure in which a face plate is attached to at least a part of the facing surface of a core part containing an air gap via a connecting face plate. Has been a deposition mask.
The vapor deposition according to claim 1, wherein the voids of the unit structure are formed in a plurality of through holes directed in a certain direction, and the unit structures are stacked so that the through holes are aligned in the same direction. mask.
The vapor deposition mask according to claim 1, wherein the core portion of the unit structure is formed of metal or carbon fiber reinforced plastic.
The vapor deposition mask according to claim 3, wherein the carbon fiber reinforced plastic is a silicon carbide fiber reinforced plastic containing silicon carbide as a reinforcing fiber.
The frame is a frame-like rectangular shape, and at the side of the frame to which the mask main body is joined, the air gap is formed to be directed from the inside surrounded by the frame to the outside of the frame. The vapor deposition mask according to any one of claims 2 to 4, wherein the unit structure is formed by a stacked columnar body on the side to which is not joined.
The vapor deposition mask according to any one of claims 1 to 5, wherein a face plate formed of a magnetic metal plate is attached to the entire outer peripheral wall of the frame containing the void.
The vapor deposition mask according to claim 6, wherein the air gap surrounded by the face plate is decompressed.
The vapor deposition mask according to any one of claims 1 to 7, wherein the mask main body is a metal mask made of a thin metal plate or a single body of a resin film.
8. The hybrid mask according to claim 1, wherein the mask body is a hybrid mask including a resin film having the opening pattern, and a metal supporting layer attached to the resin film and having an opening so as not to block the opening pattern. The vapor deposition mask according to any one of the items.
A process of arranging a vapor deposition substrate and a vapor deposition mask according to any one of claims 1 to 9 so as to overlap, and scattering of a vapor deposition material from a vapor deposition source disposed apart from the vapor deposition mask. Depositing the deposition material on the deposition substrate by
Vapor deposition methods, including:
The frame of the said vapor deposition mask is a frame-like rectangular shape, The said vapor deposition mask is erected so that the flame | frame formed in columnar shape may be intersected with a horizontal surface by laminating | stacking the said unit structure. Vapor deposition method.
Forming at least a TFT and a first electrode on a supporting substrate;
A laminated film of organic layers is formed on the supporting substrate by vapor-depositing the organic material using the vapor deposition method according to claim 10 or 11;
A method of manufacturing an organic EL display device, comprising forming a second electrode on the laminated film.